A primary consideration in the design of fuses for military purposes is to provide for maximum safety of personnel involved independently of the technical experience of the personnel handling the equipment. It is, accordingly, an object of this invention to provide a fuse assembly comprising a fuse and grenade attached thereto structured to provide for maximum security prior to deployment and which does not become armed even though the firing pin is completely unscrewed, in contrast to the M223 fuse wherein unscrewing of the firing pin causes arming. Specifically, the fuse of this invention has three safety mechanisms in addition to the safety pin and, unlike the M223, does not embody a spring which, after unscrewing of the striker pin, can push the slider to an armed position, but, on the contrary, embodies a plastic safety mechanism which keeps it in locked position, thus complying with the requirements of Stanag 4157. The M223 has but two safety mechanisms, whereas that of the instant invention has three safety mechanisms independently of the safety pin.